Spiral stitching attachment for sewing machines



Jan. 15, 1963 A. GUIDE 3,073,266

7 SPIRAL STITCHING ATTACHMENT FOR SEWING MACHINES Filed Nov. 23, 1959 5 Sheets-Sheet 1 Y -f6\- gz/ 2 1 44 I I 26\\: If

IN VE N TOR Anfiwzzy Guide BY H TTORNE Y5 A. GUIDE 3,073,266

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SPIRAL STITCHING ATTACHMENT FOR SEWING MACHINES I III 5 wmw mi m N .Z R w u m m M m M Jan. 15, 1963 Filed Nov. 23, 1959 3,073,266 SPERA'L STITCHING ATTACHMENT FOR SEWING MACHINES Anthony Guide, 23 Anderson St., Raritan, NJ. Filed Nov. 23, 1959, Ser. No. 854,813 3 Claims. (Cl. 112-2) The invention relates to a spiral stitching attachment for sewing machines wherein the attachment causes the center of the workpiece to move transversely of the di1ection of feed through the stitching mechanism of the machine resulting in a spiral line of stitching.

The attachment includes a cam member having a spiral form track thereon and a follower in the track driving the work control pivot member to move the work transversely and to provide pivotal support therefor. The cam member is intermittently driven from a part of the drive means of the sewing machine so as to move the workpiece transversely only during those intervals of time when the sewing machine needle is in its raised position and withdrawn from the workpiece, whereby the needle will not interfere with movement of the work. The contour of the cam is such as to control the movement of the pivot pin whereby the resultant spiral formed by the sewing machine has convolutions which are equally spaced part in a radial direction.

The invention finds embodiment in a preferred construction whereby the material feeding means of the sewing machine is driven by an oscillatory member and wherein the attachment includes connecting means secured tothat oscillatory member to intermittently oscillate the driving member of a one-way clutch arranged to drive the spirally formed cam. The magnitude of the oscillations transmitted to the driving member of the clutch may be manually adjusted to pre-set the spacing between spiral convolutions formed on the workpiece while maintaining uniform spacing.

It is, therefore, an object of this invention to provide a spiral stitching attachment for sewing machines wherein a workpiece is moved transversely of its normal direction of feed through the machine by means timed to effect such.

transverse movement only when the sewing machine needle is withdrawn from the workpiece.

It is another object of this invention to provide a spiral stitching attachment, as set forth, including novel drive means therefor.

It is still another obiect of this invention to provide a spiral stitching attachment, as set forth, wherein the spacing between convolutions of the spiral may be readily pre-set to any desired value within the limitation of the structure.

It is a further object of the invention to provide a spiral stitching attachment which embodies a spirally formed cam which automatically compensates for changes in the radius in which stitching occurs whereby successive convolutions are equally spaced.

A further object of this invention is to provide a novel spiral stitching attachment, as set forth, which is capable of being attached to the base of a sewing machine below the supporting table where it will be out of the way and cannot interfere with the work on the work table.

A still further object of this invention is to provide a spiral stitching attachment that is relatively simple in construction, yet efficient and reliable in operation.

Additional objects and advantages will become apparent to those skilled in the art as the description proceeds in connection with the accompanying drawing, in which:

FIG. 1 is a front elevational view of the attachment secured to a sewing machine;

FIG. 2 is a sectional view along the line 22 of FIG. 1,

illustrating the driving connection between an oscillating member of the sewing machine and the one-way clutch, parts of the clutch being broken away;

FIG. 3 is a sectional view along the line 33 of FIG. 1, showing a portion of the connection between the cam and the pivot pin;

FIG. 4 is a sectional view on the line 4-4 of FIG. 3;

FIG. 5 is a plan view, partially in section, along the line 55 of FIG. 1, showing the work holder above the table, the spiral cam below the table, and the speed reduction gearing;

FIG. 6 shows a spiral stitching track formed by the attachment;

FIG. 7 is a vertical sectional view through the oneway clutch, speed reducing mechanism, clutch mechanism, and spiral cam, along the line 77 of FIG. 5;

FIG. 8 is a plan view of the clutch mechanism in its disengaged position; and

FIG. 9 is the plan view of the clutch mechanism in its engaged position.

Referring to FIGS. 1 and 2, there is illustrated a conventional sewing machine designated generally by the numeral 10 and comprising an upper portion or head 12, a pedestal 14, and a base having a flange 16 adapted for mounting over a rabbeted opening 17 in a table 11. A belt or the like driving means 18, driven by a motor (not shown), drives the conventional wheel 20, which is secured to a shaft (not shown) extending through the upper portion or head 12-, and arranged to drive the re-' ciprocating needle 22 and the usual thread feeding means and the like. The shaft, driven by the wheel 20, further drives a drive belt or the like 24, extending inwardly through pedestal 14, to drive a lower or bobbin shaft 26 rotatably journalled on the under side of the base 16. Shaft 26 drives the bobbin and the needle feeding member (not shown), in a conventional manner.

The shaft 26 is provided with eccentrics 28 mounted thereon, which eccentrics drive connecting rods 30 and 32. The connecting rod 30 operates a rock shaft 34 to alternately lift and lower the material feeding member, while connecting rod 32 operates a rock shaft 36 to alternately move the material feeding member in a fore-and.-v aft direction, all in a well known manner. Connecting rod 32 may thus be described as an oscillatory member or element and will be so referred to hereafter.

The base 15 is provided with an enlarged boss 38 on its under side, which forms a rigid support for one of the bearings in which the bobbin shaft 26 is journalled.

The attachment of the present invention preferably comprises a frame casting 40 secured to the bottom sur- 7 the table 11 by means of a plurality of screws 46, the guideplate including an end extension 48 adapted to fit inthe usual access opening 50 below the needle (FIG. 5). The guide plate 44 is provided with an elongated slot 52, adapted to receive a plate 5'4, carrying an upstanding pivot needle 56 for pivotally supporting a workpiece, as shown in FIG. 1. The lower part of plate 54 carries a follower 58 which fits and is slidable in the elongated slot 52. The plate 54 is mounted in a groove in the lower part of the leg 60 of an L-shaped bracket, shown in FIG. 5. The longer leg 62 of the bracket extends parallel to the length of the table, and carries on the outer end thereof a pedestal 64* having a gooseneck at its upper end.

A guide sleeve 68 is pivotally mounted by means of a. pivot pin 66 on the upper end of the pedestal 64-, the

sleeve adapted to slidably receive a Work holding stem 70. The upper end of the stern carries a knob 72 by means of which it 'may be raised and lowered and tilted,

, and the lower end of the stem is hollow to fit about the end of the pivot pin 66 as shown, for the purpose of re taining a workpiece on the pivot pin.

The L-shaped bracket is carried at the upper end of a vertical link 74 passing through an elongated slot 76 in the table 11 (FIGS. 3 and and is secured to the link by means of a pair of spaced screws 78, movable in slots 80 to permit adjustment of the bracket on the link 74. The lower end of the vertical link 74 is connected to one end of a transverse link 82' through a block 84 by means of a pair of screws 86 passing through slots 88 in the lower end of link 74 and by a pair of screws 90 passing through slots 92 and one end of the transverse link 82. Transverse link 82 is connected at its inner end to the end of an operating rod 94 by means of a pair of screws 96 passing through slots 98 in the transverse link 82. The inner end of the link 82 is received in a transverse groove 100 in the upper surface of the operating rod 94, to prevent relative rotation of the link 82 thereon.

Operating rod 94 is adapted for sliding movement in a slotted guide 102 secured to the lower end of a depending support 104, which support is attached, at its upper end, to the frame casting 40 by means of screws 106. The other end of the operating rod 94 carries, on its lower surface, a cam follower 108 which operates in a spiral cam groove 110 of "a cam plate 112.

Referring to FIGS. 1, 2, 5 and 7, a transmission 114 is provided for moving the same plate 112 and the operating rod 94. The transmission comprises a housing 116, which is secured to the lower surface of the frame casting 40 by means of screws 118 passing through openings in flanges 120 integral with or connected to the housing. Transmission 114 includes a hollow output shaft 122, which depends from an opening in the lower wall of the housing as shown in FIG. 7. Output shaft .122 carries a worm gear 124 within the housing, which is driven by a worm 126 rotatable on a transverse shaft 128 supported in the walls of the housing. Worm 126 forms an extension of a sleeve carrying a worm gear 130 which meshes with a worm 132 rotatable with a horizontal shaft 134 extending transversely of the shaft 128.

One end of the shaft 134 extends through an opening in the wall of the housing, and is adapted to be driven by means of a one-way clutch 136, shown in FIGS. 2 and 7. The one-way clutch is driven by means of a pivoted operating link 138 pivotally attached to one end of an oscillating lever 140 connected by means of a split clamp 142 to the oscillatory member or element 36.

The one way clutch comprises a sleeve 144 having a collar 146 at its mid section which is secured to the shaft 134 by means of a set screw 148, to prevent relative rotation; The sleeve 144 includes an inner cup-shaped end extension 150 and an outer cuptshaped extension 152. A cam block 154 is operable within the outer cup-shaped extension 152, and includes an axial extension 156. The cam block and extension are rotatably journalled on the end of the shaft 134. The cam block includes a plurality of cam surfaces 158 adapted to receive spring-pressed rollers 160, more clearly shown in FIG. 2. A similar cam block "162 operates within the inner cupashaped extension 150, and includes an end flange 164 adapted to close the open end of the cup-shaped extension 150. The cam block 162 is freely journalled on the shaft 134, but is prevented from rotating by means of one or more dowels 166 engaging the flange 164 and an aligned bore in a wall of the housing, as shown in FIG. 7. The cam block 162 includes cam surfaces and spring-pressed rollers 168, similar to those shown on cam block 154.

A collar 170 is secured to the extension 156 of the cam block 154, and supports an upstanding stem 172, which may be threaded into the collar 170, as shown in FIG. 7. A closure ring 174 surrounds the extension 156 and is retained against the open end of the cup-shaped extension 152 by means of the collar 170. A screw, having a collar 176, retains the elements of the one-way clutch on shaft 134 against axial movement. An adjustable clamp 178 is mounted on the upstanding stem 172, as shown in FIG. 2, and is pivotally connected to one end of the operating link 138. The other end of the operating link is pivotally connected to a clamp 180 secured to the lower end of the lever 140.

Referring to FIGS. 5 and 7, the operating rod 94 is provided with an elongated slot 182 surrounding the hollow output shaft 122 for guided movement. The operating rod 94 is further guided within a guide member 184 secured to a lower wall of the housing 116. A collar 186 and a pair of spacing washers 188 surround the hollow output shaft 122, and are disposed between the operating rod 94 and the upper surface of the cam plate 112.

One end of the hollow output shaft 122 passes through an opening 190 in the cam plate 112 which coincides with the axis of the spiral cam groove 110.

The clutch member is shown in greater detail in FIGS. 7, 8 and 9, to which reference is now made. The clutch member comprises a hub 196 fixed to the hollow output shaft 122 by a set screw 198, having an integral radial extension 200 joining the hub to a peripheral friction ring portion 202. The friction ring portion 202 is separated from the hub throughout the major porton of its circumferential extent and on the side thereof, opposite the integral extension 200, the friction ring portion 202 is split as at 204 to provide a pair of free terminal end portions thereof. A cam lever 206 is pivoted at 208 near one end of the terminal ends of the friction ring portion 202 and extends somewhat downwardly (see FIG. 7) to position its end 210 substantially below the clutch element. The end 210 is provided with a radially extending adjustable stud 212. The other end of the cam lever 206, adjacent the pivot 208, is provided with an angular end surface 214 terminating in a projection 216 at the outer edge of the lever. The terminal end 218 of friction ring portion 202 extends axially downwardly a greater distance than the terminal end to which lever 206 is pivoted so that its end face 220 is in position to be engaged by the projection 216 of the lever 206.

When the cam lever 206 is positioned with its end 210 inwardly toward the axis of shaft 122, the projection 216 of the cam lever 206 moves away from the end surface 220 of the end 218 of friction ring portion 202, thus permitting the ring portion to resiliently contract with clearance between its outer periphery and the inner surface of the cup 192. Thus, the cup 192 may rotate freely relative to the clutch ring portion 202 and shaft 122.

When the end 210 of lever 206 is moved radially outwardly to the position of FIG. 9, the projection 216 of the cam lever engages the end surface 220 of the friction ring portion 202 to force the terminal ends of the friction ring portion apart and extend the same into tight frictional engagement with the inner periphery of the cup 192 to thus frictionally clutch the cup 192 and cam plate 112 to the shaft 122.

The clutch element is actuated by a clutch actuating member 222, depending below the clutch element, generally in the form of a frustum of a cone. Member 222 is slidably mounted on a spindle 224, being limited in its downward movement by a collar 226 engaging the larger base of the member 222. Collar 226 is secured to the spindle 224 by a set screw 228. The upper end of the spindle 224 passes through the hollow output shaft 122, and through a helical spring 230 in a counterbore in said shaft. ,The spring 230 engages a pin 232 on the upper end of the spindle 224 and a shoulder 234 at the bottom and spindle 224 against the upward force of spring 2371i.

effecting a downward movement of the clutch actuating member 222 and unclutching of the clutch element.

In the description of operation which follows, the workpiece is a brassiere cup in which it is desired to produce a spiral stitch, but it is to be understood that the apparatus could equally well be employed for producing other articles, or to spirally stitch any flat workpiece.

In operation, it may be assumed that the cam plate 112 occupies the position shown in full lines in FIG. 5, in which the cam follower 108 occupies the outer end of the spiral cam groove 110, which brings the bracket legs 60-62 to their right hand position and the pivot needle 56 adjacent the reciprocating needle 22 of the sewing machine FIG. 1). The work holding stem 70 may be raised by the knob 72, and a brassiere cup 246 may be centered on the pivot needle '56 with the concave side upwardly, the needle 56 piercing the cup. The holding stem 70 may then be lowered so that the hollow lower end thereof fits over the pivot needle 56 to retain the cup on the needle 56 and yet permit rotation of the cup. In this position, the central area of the cup will lie below the stitching needle 22, and the presser foot (not shown) may be lowered into contact with the workpiece. The reciprocating needle 22 would then be directly over the point 248 in FIG. 6. Assuming that the pedal 240 is in its raised position, the helical spring 230 will draw the clutch actuating member 222 to its uppermost position shown in FIG. 7, which causes the adjustable stud 212 to ride up on the tapered peripheral surface of the member 222 to force the cam lever 206 to its clutch engaging position shown in FIG. 9 in which the free ends of the friction ring portion 202 are spread apart to bring the outer peripheral surface thereof into frictional engagement with the internal Wall of the cup 1%, thus providing a driving connection between the output shaft 122 and the cam plate 112. When the sewing machine is set into operation by the usual switch, not shown, the reciprocating needle 22 will proceed to form stitches 250 in the workpiece 246, which stitches, because of the pivotal support of the workpiece by the needle 56, would ordinarily describe a circle. However, the pivot needle 56 is concurrently moved transversely of the direction of stitching, being guided in the slot 52 by the follower 58, which results in the formation of the spiral pattern shown in FIG. 6, which spiral pattern terminates at the point 252. If desired, the clutch member may be disengaged when the reciprocating needle reaches the point 252 by depressing the pedal 240 and continuing the operation of the sewing machine. As the pivot needle 56 will thereupon remain fixed, an additional circular closing loop 254 may be formed, providing a more pleasing appearance. Similarly, a circular loop can be formed at the center by operating the sewing machine to produce a loop or circle of stitching prior to engagement of the clutch member for the spiral attachment.

'In operation of the sewing machine, the bobbin shaft 26 has a rotary motion, and, because of the connection 28 and 32, produces an oscillatory motion of the rock shaft 36. The oscillatory motion of rock shaft '36 produces a concurrent oscillatory movement of the cam block 154 of the one-way clutch 136 through the lever 140, pivoted link 138, and upstanding stern 172. The amplitude of the oscillating movement of the cam block may be varied by varying the distance of the adjustable clamp 178 from the axis of the cam block 154. Maximum amplitude of oscillation is obtained by disposing the clamp 178 adjacent the collar 170 as shown in FIG. 2, while decreased amplitude of oscillation is obtained by increasing the distance of the clamp 17 8 from the collar 170.

With reference to FIG. 2, it will be noted that the clockwise oscillation of the cam block 154 will allow the rollers 16% to ride toward that portion of the cam track 158 more remote from the cup-shaped end 152, resulting in a slipping action between the cam block 154 and the cup-shaped end 152. Oscillation of the cam block 154 in a counterclockwise direction causes the rollers 160 to become wedged in the angle formed by the cam tracks 158 and the inner wall of the cup-shaped end 152, resulting in a clutching action and causing a counterclockwise incremental movement of the clutch housing formed by the collar 146 and cup-shaped ends 150 and 152. Since the collar 146 is securely fastened to the shaft 134 through the set screw 143, the shaft 134 is given a slight rotative movement in a counterclockwise direction. The cam rollers 168 cooperate with the cam block 162 and the inner cup-shaped end 154 on the other end of the oneway clutch 136 to permit free movement of the clutch housing in a counterclockwise direction as viewed in FIG. 2, and to prevent movement in a clockwise direction. It is een, therefore, that the shaft 134 is rotated intermittently in a single direction by a step-by-step movement. By means of the reduction gearing 132, 130, 126 and 124, the output shaft 122 paitakes of a similar stepby-step movement at a reduced speed, the reduction gearing being designed, in a preferred embodiment, to provide a reduction in the ratio of 400 to 1. With the clutch member in the engaged position as shown in FIG. 9, the cam plate 112 is caused to rotate in a counterclockwise direction, as viewed in FIG. 5, which illustrates in solid lines the starting position. The cam groove is so configured that rotation thereof in a counterclockwise direction as seen in FIG. 5 results in a movement of the cam follower 103, operating rod 94, and bracket legs 60-62 toward the left, resulting in the movement of the pivot needle 56 away from the stitch forming needle 22. Because of the spiral form of the cam groove 11%, the rate of movement of the pivot needle 56 from the stitching needle 22 decreases in accordance with its distance traveled. From an inspection of FIG. 6, it is evident that each convolution of stitching includes a greater number of stitches as the convolutions progress away from the center. It is necessary, therefore, to move the pivot needle 56 at a slower rate in proportion to its distance from the stitching needle 22 in order to maintain the spacing between successive convolutions of the spiral row of stitching substantially constant. The particular cam groove shown is designed to accomplish this result.

After a workpiece 246 has been spirally stitched, the pressing foot of the sewing machine may be raised and the workpiece removed. Depression of the pedal 240 will release the clutch, whereupon the cam plate may be returned to its starting position shown in full line in FIG. 5 by manual operation of the bracket legs 6il-62, which can be shifted toward the right in FIG. 5 by a light manual effort.

As explained above, each oscillation of the rock shaft 36 produces a concurrent step-bystep movement of the shafts 134 and 122, and the extent of such movement can be varied by shifting the clamp 178 on the upstanding stem 172. From the foregoing, it is evident that the adjustment shown in FIG. 2 provides a maximum spacing between successive convolutions of the spiral stitching of FIG. 6, while smaller spacing is obtained by moving the clamp 178 toward the position shown in broken lines.

As explained above, rock shaft 36 operates the material feeding member in a fore-and-aft direction, which operation is timed to occur only when the stitching needle 22 is out of engagement with the workpiece being stitched. By virtue of the connection of the one-way clutch 130 with the rock shaft 36, rotational movements are imparted to the shaft 134 only during those movement of the lever which also drive the material feeding member to feed the material through the stitch forming mechanism, and therefore the spiral stitch forming cam is rotated only during those intervals in which the needle is disengaged from the workpiece. If the shaft 134 were rotated continuously, the attachment would attempt to impart continuous transverse movement to the workpiece even during the intervals of time when the stitching needle 22 passes therethrough and the result would be a stretch- 7 ing or distortion of the workpiece and even possible damage to the stitching mechanism. By the mechanism of the present invention, such defects are eliminated.

From the foregoing, it is evident that applicant has devised a novel spiral stitch forming attachment which can be quickly and readily. attached to an existing sewing machine with a minimum requirement of modification, and which attachment is capable of a wide range of spiral patterns, combined, if desired, with circular patterns.

While a single specific embodiment of the invention has been shown and described herein, it is to be understood that the same is merely illustrative. It is conte plated that the invention, as defined in the appended claims, encompasses other modifications.

I claim:

1. An attachment for a sewing machine having stitchforming means including a reciprocating needle, means for linearly feeding material past said stitch-forming means in a pre-determined direction, and drive means ineluding an oscillating member, said attachment comprising: a frame having an attaching portion adapted to be attached to a lower part of the sewing machine; a work-controlling pivot member adapted to be slidably mounted on said sewing machine for movement in a direction transverse to said pie-determined direction; a transmission housing fixedly attached to said frame; speed reducing gearing within said housing including a power output shaft extending from the housing on a fixed axis; a driving connection connected to said speed reducing gearing and extending past said attaching portion for connection to said oscillating member; said driving connection including means for intermittently driving said speed reducing gearing in timed relation to reciprocation of said needle; means defining a spiral cam track attached to said power output shaft and rotatable therewith; and movement transmitting means, including a cam follower :errgaging said cam track, to linearly move said workcontrolling pivot member relative to said reciprocating needle.

2. An attachment for a sewing machine as recited in claim 1, in which the movement transmitting means includes an elongated slot forming means, the power output shaft extending through said slot for forming a guiding means for the movement transmitting means.

3. An attachment for a sewing machine as recited in claim 1, in which said driving connection includes a oneway clutch and means for selectively varying the arcuate extent of the oscillating movement transmitted to the oneway clutch.

References Cited in the file of this patent UNITED STATES PATENTS 2,547,639 Gensheimer Apr. 3, 1951 2,551,261 Gensheimer May 1, 1951 2,764,112 Happe Sept. 25, 1956 2,787,229 Medynski Apr. 2, 1957 2,854,935 Benink et a1 Oct. 7, 1958 2,857,865 Guide Oct. 28, 1958 2,863,407 George Dec. 9, 1958 2,938,477 Graham et al May 31, 1960 FOREIGN PATENTS 525,946 Italy May 12, 1955 

1. AN ATTACHMENT FOR A SEWING MACHINE HAVING STITCHFORMING MEANS INCLUDING A RECIPROCATING NEEDLE, MEANS FOR LINEARLY FEEDING MATERIAL PAST SAID STITCH-FORMING MEANS IN A PRE-DETERMINED DIRECTION, AND DRIVE MEANS INCLUDING AN OSCILLATING MEMBER, SAID ATTACHMENT COMPRISING: A FRAME HAVING AN ATTACHING PORTION ADAPTED TO BE ATTACHED TO A LOWER PART OF THE SEWING MACHINE; A WORK-CONTROLLING PIVOT MEMBER ADAPTED TO BE SLIDABLY MOUNTED ON SAID SEWING MACHINE FOR MOVEMENT IN A DIRECTION TRANSVERSE TO SAID PRE-DETERMINED DIRECTION; A TRANSMISSION HOUSING FIXEDLY ATTACHED TO SAID FRAME; SPEED REDUCING GEARING WITHIN SAID HOUSING INCLUDING A POWER OUTPUT SHAFT EXTENDING FROM THE HOUSING ON A FIXED AXIS; A DRIVING CONNECTION CONNECTED TO SAID SPEED REDUCING GEARING AND EXTENDING PAST SAID ATTACHING PORTION FOR CONNECTION TO SAID OSCILLATING MEMBER; SAID DRIVING CONNECTION INCLUDING MEANS FOR INTERMITTENTLY DRIVING SAID SPEED REDUCING GEARING IN TIMED RELATION TO RECIPROCATION OF SAID NEEDLE; MEANS DEFINING A SPIRAL CAM TRACK ATTACHED TO SAID POWER OUTPUT SHAFT AND ROTATABLE THEREWITH; AND MOVEMENT TRANSMITTING MEANS, INCLUDING A CAM FOLLOWER ENGAGING SAID CAM TRACK, TO LINEARLY MOVE SAID WORKCONTROLLING PIVOT MEMBER RELATIVE TO SAID RECIPROCATING NEEDLE. 